c_cpp c中的示例扫描功能可以打印所有数字

Posted 2021-05-14

#include <stdio.h>

// Print all sequence of digits in a string in C
void print_all_digit(const char* input)
{
  int on = 0;
  goto BASE;
BASE:
  switch(*input)
  {
    case '\0':
          return;
    case '0':
    case '1':
    case '2':
    case '3':
    case '4':
    case '5':
    case '6':
    case '7':
    case '8':
    case '9':
         on = 1;
         putc(*input++, stdout);
         goto BASE;
    default:
    // Picks apart digit sequence by newline
        if(on)
        {
          putc('\n', stdout);
          on = 0;
        }
        input++;
        goto BASE;
  }
}

int main(void) {
  print_all_digit(" .  56456 5 5 6 6 fjh43f89u93hdjdf354534fdjfjji5hfh54j43324jcjdshd9erf934urfh2r38f94u9u2f3jdif099 .  fehwe33");
  return 0;
}